diff --git a/include/boost/python/detail/is_xxx.hpp b/include/boost/python/detail/is_xxx.hpp
index ad888b84..0faea999 100644
--- a/include/boost/python/detail/is_xxx.hpp
+++ b/include/boost/python/detail/is_xxx.hpp
@@ -12,6 +12,7 @@
 
 # if defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
 # include <boost/type_traits/is_reference.hpp>
+# include <boost/type_traits/add_reference.hpp>
 
 #  define BOOST_PYTHON_IS_XXX_DEF(name, qualified_name, nargs)      \
 template <class X_>                                                 \
@@ -20,7 +21,7 @@ struct is_##name                                                    \
     typedef char yes;                                               \
     typedef char (&no)[2];                                          \
                                                                     \
-    static X_ dummy;                                                \
+    static typename add_reference<X_>::type dummy;                  \
                                                                     \
     template < BOOST_PP_ENUM_PARAMS_Z(1, nargs, class U) >          \
     static yes test(                                                \
diff --git a/test/implicit.cpp b/test/implicit.cpp
index b56e6b10..c4728548 100644
--- a/test/implicit.cpp
+++ b/test/implicit.cpp
@@ -20,8 +20,18 @@ int x_value(X const& x)
 
 X make_x(int n) { return X(n); }
 
+
+// foo/bar -- a regression for a vc7 bug workaround
+struct bar {};
+struct foo
+{
+    virtual void f() = 0;
+    operator bar() const { return bar(); }
+};
+
 BOOST_PYTHON_MODULE(implicit_ext)
 {
+    implicitly_convertible<foo,bar>();
     implicitly_convertible<int,X>();
     
     def("x_value", x_value);